Characterization of Asphalt Binders Modified with Hydrated Lime and Limestone Dust

Abstract

The mixture of asphalt and filler called asphalt binder is an adhesive and packing material in asphalt mixture. In this paper, the influence of different filler sorts such as limestone dust and hydrated lime, and different rates of limestone dust and hydrated lime such as 2:1, 1:1 and 1:2 at the same mass ratio of filler/asphalt (1.0) on the asphalt binder’s properties has been studied. The paper gives a description of the most commonly used conventional tests, such as Penetration and Softening Point, and a more detailed description of the viscoelastic behavior and dynamic testing of bitumen by way of Brookfield viscometer and Dynamic Shear Rheometer (DSR). The contrasts among different test results were presented. It is found that there are a decrease in penetration and an increase in softening point with increasing hydrated lime content. The viscosity also increases obviously with the mass of hydrated lime increases. The DSR results show that hydrated lime can increase asphalt binders' anti-shear stress and G*/sinδ, and are helpful to its properties at high temperature. The four tests results were also incorporated to evaluate the temperature susceptibility and the rheological characteristics of asphalt binders.